1. Field of the Invention
The present invention relates generally to waveguide devices, and more particularly, to size and guide wavelength modification for waveguide devices.
2. Description of Related Art
A significant disadvantage of conventional waveguides is their size and large guide wavelength. For example, WR-975 waveguides (which can be obtained from such companies as Mega Industries and are designed for use between the frequencies of 0.75 and 1.12 GHz) has a width of 9.75 inches and a height of 4.875 inches. The height of a conventional waveguide can be reduced without affecting the fundamental-mode cutoff frequency and guide wavelength, but the same is not true of its width.
Moreover, reductions in cross-sectional area in ridged waveguides require that the gap between the ridges be on the order of one-quarter the height of the waveguide. This substantially reduces the power-carrying capacity of the waveguide, leaving it susceptible to breakdown at high power levels. In addition, the guide wavelength in ridged waveguides is approximately equal to that in other conventional waveguides, so that nearly equal lengths of either ridged or conventional waveguides are required to achieve a given phase shift.